84 M. Foslie. 



places on open coasts, having a stipe 2 m. high by a dia- 

 meter at the base of 4 — 5 cm., tapering towards the top, 

 and a lamina only 40 cm. long; but in sheltered places a 

 short stipe, often only 30 — 50 cm. high, almost destitute of 

 cork layer, less solid and proportionally feeble, and a lamina 

 of the same length as the stipe, or longer. With regard to 

 the muciferous lacunae by L. digitata I have before stated 

 their variation, and also that they most often are wanted 

 by specimens of f. genuina, and often also by the other forms 

 from the open coast of Finmarken. I have numerous such 

 specimens. And I have of late had the opportunity of seing 

 that they not always exist by specimens from other places. 

 By the kindness of Geo. W. Traill, Joppa, and J. "W. 

 Cursiter, Kirkwall, I have got some almost fresh speci- 

 mens of L. digitata from the Orkney Islands. They are most 

 nearly related to f. genuina, and muciferous lacunae are wan- 

 ting. On the other hand, by specimens from the southern 

 coast of Norway the lacunas mostly exist and are as a rule 

 pretty numerous. The same is the case by the specimens, 

 that I have referred to f. stenophylla, muciferous lacunas so- 

 metimes exist sometimes are wanting. Therefore, I am still 

 inclined to denie its right to be regarded as a separate spe- 

 cies, and keep it as a form of L. digitata. 



A form of L. digitata appears in rock-pools between 

 tides. It is most nearly related partly to f. genuina, partly 

 to f. ensifolia, and also much varying. The stipe has a 

 height of 1 — 2 cm. by a lamina 1 m. and more in length, 

 or the stipe becomes about 50 cm, heigh, with shorter la- 

 mina, more or less cut up in broader or narrower segments, 

 and the base sometimes cordate, sometimes cuneate. It is 

 annual, at least at Tromso, arising in April and disappearing 

 in November. 



The species in question is litoral and sublitoral, living 

 chiefly in the upper part of the sublitoral zone from extreme 



